The present invention makes a contribution to seat furniture articles that are used daily, in particular stools and chairs.
It concerns seat furniture comprising an adjustable frame, which is quickly and easily adjustable in regard to height and inclination and thus can meet a wide range of ergonomic requirements and large numbers of which can be transported and stored due to the fact that the furniture can be stacked.
To date a number of different adjustable seat furniture types are known that allow the adjustment of one or a plurality of components; some of them can be stacked.
For example, U.S. Pat. No. 5,516,197 refers to an adjustable chair in which some of the legs can be adjusted. The design of this chair is such that the adjustment of height and seat inclination appears to be slow and labor-intensive.
U.S. Pat. Nos. 2,098,888, 2,169,32 and 4,240,663 are also known and describe stackable chairs but do not have any adjustment mechanisms that go beyond form or materials based flexibility.
U.S. Pat. No. 2,745,468 shows a flexible chair that is comprised of a rigid frame and a seat with a back—made of one piece—which can move back and forth slightly on said frame. This chair does not provide any additional devices for adjusting the height or fixing any positions.
Also known is U.S. Pat. No. 3,328,075 which introduces a frame that allows chairs to be coupled on the sides and can be stacked, but does not provide any adjustment devices or adaptation possibilities to different ergonomic requirements.
U.S. Pat. No. 4,238,097 shows a chair for orchestra conductors or contrabass players that is adapted to the adjustment combinations of certain stage pedestals. It shows devices that are operated individually by hand. The seat rests on a central, telescopically adjustable center column, however, its inclination cannot be adjusted and the structure does not allow for any stacking.
Furthermore, U.S. Pat. No. 4,306,750 is known that introduces a chair that was developed especially for musicians. Although it can be stacked, it does not provide any adjustment mechanisms at all.
U.S. Pat. No. 4,671,570 presents a stackable chair. The shape of the seat area can be adjusted; however, there is no device for height adjustment.
Finally, U.S. Pat. Nos. 5,035,466 and 5,048,893 should be mentioned that introduce chairs whose seats rest on a column whose length can be adjusted and whose lower end comprises braces that are fastened in a star-shaped arrangement and provide for secure standing. However, these chairs cannot be stacked on other chairs of the same type.
The invention that is introduced here offers different advantages and conveniences:
It comprises position adjustment devices that allow for the independent adjustment of the height of the front or rear chair legs, which in turn results in an adjustment of the height and inclination of the seat. The four legs can be adjusted simultaneously, or the front or rear pairs of legs can be adjusted successively in random order.
The adjustment is easy and quick. It can be done with one hand. It may be possible to use a foot.
The configuration also ensures stacking.
The upper and lower articulated hinges that are integrated in the frame permit each adjustment while the support area on the floor does not change.
The adjustment devices of the legs and the upper and lower articulated hinges provide this seat furniture with a high degree of versatility for the user as well as for service personnel without affecting its simple, exterior appearance.